The form of a verb should be used to distinguish between actions completed in the immediate past and actions completed before a specific time. a. simple past b. infinitive c. irregular d. past perfect

Simple past tense verbs are used for completed actions that happened before now. It's the basic form of past tense, used to say when something happened. The action is in the past, either recently or distantly. For example: "We lived in Chicago during the 1980s."

Infinitive verbs are the basic form of verbs, with the word "to" in front of it. There are no conjugations used with it (such as -ed, -ing, or -s). For example: "Sherry wanted to score more points than her brother in basketball."

Irregular verbs are those that don't use the typical -ed, -d, or -ied forms of spelling of past simple or past participles. For example: "I would like to drink more of your raspberry lemonade. I drank some yesterday and it was amazing!" (We wouldn't add an -ed to drink like most verbs to say "drinked"; instead, we would use the irregular verb drank.)

Past perfect verbs are those used for actions that were completed at some point in the past. They're used when talking about something that occurred before something else. For example: "Mark did so well on the math test because he had been tutored all month."

The best answer would be D. past perfect since you're using a verb that occurred before another action in the past.